Why are there background noises in the sound of moving pictures or sound that recorded in a car?

Why are there background noises in the sound of moving pictures or sound that recorded in a car?

Select [Recording] on [Volume Control Properties] to set the level of the microphone a little lower.The internal microphone is a non-directional microphone. Therefore, it also records noises around you. In addition, the input level of the microphone is set a little higher

To improve the situation, on [Volume Control], select [Option]->[Property] and select [Adjust volume for]->[Recording]. Then, set the sound volume of the microphone a little lower. This makes the level of conversation volume lower with the background noise reduced fairly.

[Remark]The level of noise varies from one person to another.Since the driving noise cannot be eliminated totally, noises contained in the sound cannot be removed completely.In addition, not only in a moving car, if there is any noise around you, the sound may contain noises as well.